1. Technical Field
The present invention relates to a driver circuit for a stepping motor, which includes two coils and has drive voltages with different phases applied to these two coils so that a rotor driven by the coils is rotated.
2. Related Art
Among the various types of motors available, one representative type of motor capable of precisely determining position is a stepping motor. Stepping motors are widely utilized in various apparatuses, for example, in focusing and anti-shake mechanisms in cameras and for positioning in machine tools.
The stepping motor is generally driven by changing the rotating position of the rotor by a current ratio to two stator coils. Therefore, if the rotor is rotated in accordance with the phase of current to the coils, the rotor rotates a predetermined amount regardless of the amount of current to the coils. Accordingly, the amount of current to the coils is generally set sufficiently large so that the rotor can rotate reliably.